<!doctype html>
<html>
<head>
<meta charset="utf-8">
<script>
"use strict";

const p = document.createElement("p");
document.documentElement.appendChild(p);
const shadowRoot = p.attachShadow({mode: "open"});
const textarea = document.createElement("textarea");
shadowRoot.appendChild(textarea);
textarea.defaultValue = "|";
</script>
</head>
<body></body>
</html>
